In addition to being grouped into four types human blood is

In addition to being grouped into four types, human blood is grouped by its Rhesus (Rh) factor. Consider the figures below that show the distributions of these groups for Americans.

                0              A             B             AB

Rh+        37%        34%        10%        4%

Rh-         6%          6%          2%          1%

Choose 1 American at random. Find the following probabilities. Enter your ansers as decimals rounded to 3 decimal places.

A person has type A blood, given that the person is Rh+.

P (type A blood, given that the person is Rh+)= ?

Solution

In addition to being grouped into four types, human blood is grouped by its Rhesus (Rh) factor. Consider the figures below that show the distributions of these groups for Americans.

O

A

B

AB

Rh+       

37

34

10

4

85

Rh-        

6

6

2

1

15

43

40

12

5

100

Choose 1 American at random. Find the following probabilities. Enter your ansers as decimals rounded to 3 decimal places.

A person has type A blood, given that the person is Rh+.

P (type A blood, given that the person is Rh+)

=34/85 = 0.400